Question: In the diagram below, which two angles form a linear pair.
$\angle 7$ and $\angle 8$
$\angle 6$ and $\angle 5$
$\angle 7$ and $\angle 5$
$\angle 6$ and $\angle 7$
Graph: A line $Q-P-T$ runs horizontally through point $P$, with ray $P-R$ extending up-left, ray $P-S$ extending up-right, and ray $P-U$ extending down-right; the angles around $P$ are labeled $8$ on the left upper side, $7$ on the right upper side, $6$ on the lower left side, and $5$ on the lower right side. position_hint=center
1. **State the problem:** Identify which two angles form a linear pair in the given diagram.
2. **Recall the definition:** A linear pair consists of two adjacent angles whose non-common sides form a straight line, summing to $180^\circ$.
3. **Analyze the diagram:** The line $Q-P-T$ is horizontal through $P$. Angles $8$ and $7$ are above the line, angles $6$ and $5$ are below.
4. **Check pairs:**
- $\angle 7$ and $\angle 8$ share vertex $P$ but are on opposite sides of the line, not adjacent.
- $\angle 6$ and $\angle 5$ are adjacent below the line but their non-common sides do not form a straight line.
- $\angle 7$ and $\angle 5$ are not adjacent.
- $\angle 6$ and $\angle 7$ are adjacent and their non-common sides lie along the straight line $Q-P-T$.
5. **Conclusion:** $\angle 6$ and $\angle 7$ form a linear pair.
**Final answer:** $\boxed{\angle 6 \text{ and } \angle 7}$